Question: What do humans in the field of work leprosy do for a living?
Paraphrase: People who work in the field of leprosy do what for a living?
SPARQL (Wikidata):  select distinct ?sbj where { ?sbj wdt:P101 wd:Q36956 . ?sbj wdt:P31 wd:Q5 } 
Answer: Gerhard Armauer Hansen, Anton Rolandsson Martin, Nicole Boucart, James W McKean